About Parkinsons Disease
Parkinson’s disease (PD) is a progressive, neurodegenerative disease that belongs to the group of conditions called motor system disorders. PD cannot yet be cured and sufferers get worse over time as the normal bodily functions, including breathing, balance, movement, and heart function worsen.
Parkinson’s disease most often occurs after the age of 50 and is one of the most common nervous system disorders of the elderly. The disease is caused by the slow deterioration of the nerve cells in the brain, which create dopamine. Dopamine is a natural substance found in the brain that helps control muscle movement throughout the body.
Who gets PD?
Parkinson’s disease affects both men and women
but occurs about 50% more in men than women.
The average age for the onset of PD is 60 years old,
however 5 – 10% of cases, called “early onset,” begin as early as 40 years old.
The National Institute of Neurological Disorders and Stroke estimates that close to 500,000 people in the United States have PD,
although most other estimates run as high as 1,00,000 people. Approximately 50,000 Americans are diagnosed each year.
The reason the numbers are approximate is that there is no set of guidelines to measure Parkinson’s disease and therefore, in this country, no national registry of cases.
People with PD have about the same life expectancy as the normal population, however complications during the late stages of the disease can lead to choking, pneumonia, and falls that can be fatal. The disease progresses at different rates in different people. A more severe progression is often seen in people who develop PD at an earlier age.
What Causes PD?
Despite intense research efforts around the world, the molecular causes of Parkinson’s disease are still unclear. What doctors and scientists do know is that PD is caused by the progressive loss of dopamine brain cells (neurons) in a part of the brain called the substantia nigra, which produces the chemical dopamine.
As the cells die, less dopamine is produced and transported to the striatum, the area of the brain that co-ordinates movement.
How is PD treated?
Treatments are available only for the symptoms of Parkinson’s disease. None of the currently available treatments can halt or even slow the loss of neurons in Parkinson’s disease.
One of the most effective and widely used treatments for the symptoms of PD is carbidopa-levodopa.
Levodopa, also called L-dopa, is a drug that is converted into dopamine in the brain.
Levodopa is often combined with carbidopa, which improves the action of levodopa and reduces some of its side effects, particularly nausea.
The side effects of L-dopa, with or without carbidopa, are considerable and can include Dyskinesia (muscle spasms), low blood pressure, arrhythmia (abnormal heart rhythms), gastrointestinal problems, nausea, hair loss, sleep disorders, confusion, anxiety and hallucinations.
Within 4 – 6 years of treatment with L-dopa, the effects of the drug in many patients begin to last for shorter periods of time after a dose (called the “wearing off effect”). The duration of the “on” state becomes shorter and “wearing off” happens sooner. The “wearing off” state can result in a tremor or slowness in movement, painful muscle spasms that can cause contortions in the neck, jaw, midsection, eyes and feet. In some patients, the “wearing off” states are predicable, allowing the patient to plan accordingly. For others it is unpredictable. Unfortunately, doctors have yet to understand why these fluctuations are predictable in some patients and not in others. In response to the “wearing off effect,” patients may choose to increase the dosage of levodopa, or frequency they take it, but in doing so they face an increased risk of dyskinesia.